The present invention relates to an image reading apparatus for applying light onto a document and receiving light reflected therefrom to thereby read an image of the document.
There is known an image reading apparatus equipped with an ADF for feeding a document to a document table, and a scanner for reading an image from the document fed to the document table. The scanner includes a carriage movable along rails. The carriage incorporates, for example, a lamp for illuminating a document, and a mirror for transmitting light reflected from the document.
The image reading apparatus operates in the following two modes. In a first mode, a document is fed to the document table and stopped at a predetermined reading position by the ADF, and has its document surface scanned by the scanner while the carriage of the scanner is being moved along the document table. In a second mode, a document is moved onto the document table by the ADF, with the carriage of the scanner stopped at the predetermined reading position, whereby the document surface of the document is scanned.
In the second mode, however, there is a problem in which the vibration of a driving motor for driving the ADF that feeds a document is transmitted to the rails via the housing of the carriage, with the result that the carriage may jump from the rails to thereby vibrate the mirror mounted thereon, which may cause a blur in a resultant read image. This problem is conspicuous when the document feed speed of the ADF is increased to execute high-speed reading.
The present invention has been developed in light of the above, and aims to provide an image reading apparatus capable of reliably reading an image of a document at high speed.
To attain the object, an image reading apparatus according to an embodiment of the invention comprises: a housing having an upper surface which forms a document table; a document feeder attached to the housing to cover the document table, and configured to feed a document to the document table; a carriage provided in the housing such that it can move along the document table, the carriage being provided with a light source which illuminates the document, and an optical member which transmits light reflected from the document; a light receiving element which receives the reflected light transmitted via the optical member; a support member attached to the housing and supporting the carriage such that the carriage can move along the document table; a fixing mechanism which fixes the carriage at a reading position; and a vibration-absorbing member which prevents vibration, generated by a driving section provided for the document feeder, from being transmitted to the carriage.
Furthermore, an image reading apparatus according to the embodiment of the invention comprises: a housing having an upper surface which forms a document table; a document feeder attached to the housing to cover the document table, and configured to feed a document to the document table; a carriage provided in the housing such that it can move along the document table, the carriage being provided with a light source which illuminates the document, an optical member which transmits light reflected from the document, and a case containing the light source and the optical member; a light receiving element which receives the reflected light transmitted via the optical member, and subjects the received light to photoelectric conversion; a rail fixed to the housing, the rail mounting thereon the case of the carriage such that the case can slide along the document table; and an electromagnet which magnetically holds the case of the carriage when the case assumes a reading position while the carriage is sliding along the rail, thereby fixing the carriage at the reading position.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.